Reversing device for combustion-engines.



W. SEGK.

REVERSING DEVICE FOR COMBUSTION ENGINES.

' APPLICATION FILED OCT. 6, 19 09. LUQQAQ; Patented Apr. 7, 1914.

3 SHEETS-SHBET l.

Fig. i

Fig.2

Wfimesses= i lm'emmca- 40. K M .44 41M W. SBOK. REVERSING DEVICE FORCOMBUSTION ENGINES.

APPLICATION FILED OCT. 6, 1909.

1,092,404. Patented Apr. 7, 19M

3 SHEEN-sum 2.

Witnesses:

dmvzmw W. SBGK.

REVERSING DEVICE FOR COMBUSTION ENGINES.

A PPLIGATION FILED OCT, 6, 1909.

LQQZAQQ, Patented Apr. 7, 1914 3 SHEETS-SHEET 3.

Witnesses: Hnvenwh @Flll-QE.

"NELLY SECIK, 0F IBERLINJVILMERSDORF, GERMANY. ASSIGNOB TO THE FIRM OFROBERT BOSCH, 0F STUTTGAR-T, GERMANY.

REVERSING DEVICE FOR COMBUSTION-ENGINES.

Specification of insane a.

Application filed October 6, 1809.

To all "whom it may concern Be it known that I. WiLLY Snort, engineer, acitizenof the German Empire, residing at Helmstedterstrasse 5,Berlinilmcrsdorl' Gerni L do hereby declare that l have invented a i'iewand useful Reversing Device for Combustion-Engines, the nature of whichinvention and in what manner the some is to be performed areparticularly described and ascertained in and by'the followingstatement.

in many instances where combustion en gines are employed it is necessaryfor the machinery driven by su h engines to reterse the direction ofremluti'on, as is the rss for instance with vehicles and vessels .lrivenby motor power.

l'Vith two cycle motors it is possible as is known, to reverse therotation of a running mot-or by great skill by restarting the ignition.which had been interrupted for stop ping the engine, shortly before theengine comes to a full stop, after having prevmusly brought thecontactor into such a position.

that the first of the renewed ignitions will occur so early as toreverse the piston before it has reached its inner-dcad pointanclthusalso reverse the direction of rotation of the crank shaft. With muchpractice this procedure will be successful in many in stances; generallyhowever the machine will be thereby unintentionally stopped. it theproper moment for restarting the ignition is not observed exactly, as ifit be started too early, the counterpressure ofthe explosion producedmay be just great enough to counteract and compensate the momentum ofthe moving masses, and not be sutficient to accelerate the same in theopposite direction: the machine will therefore come to a standstill: @nthe other hand onenot sufficiently practised in this operation may alsolet the machine stop before even starting the ignition; which may easilyoccur by wrongly estimating the speed of the revolution. But even notconsidering the possible or to speak more correctly probablenon-success, this method has the great disadvantage of requiring thewhole attention of the attendant at a moment where he surely needs itfor other purposes, as for steering or landing his boat. Furthermore forbeing able to properly observe the speed of the revolution of his enginehe must have a close access to the same without any obstruction orcover.

Letter -P t n Patented Apr. "2, 1914.

Serial No. 521,350.

These two requirements can hardly ever be met, wherefore only very fewattempts have been made to avoid. the use of reversing gears orswiveling blade propellers by reversing the engines employed in. motorcar or motor vessel construction. v

The subject of the present invention is an arrangement for enabling afully reliable reversing of combustion engines. For facilitating thedescription the arrangement is referredto in the hereinafter followingdescription as attached to a two cycle engine; it may however also beattached to a four cycle cngina which is titted with a valve gearsuitable for this respective purpose.

Figure l is a vertical sectional View of the device in runningcondition. Fig. 2 is a. top plan view of the device, part being shown insection for the sake of clearness. Fig. 3 is a sectional view similar toFig. 1. and at right angles thereto. Fig. 4 is a similar view to Fig. 1,the parts being shown as occupying their positlon'when the device isrunning slowly or when it has ceased running. Fig. 5 is a plan view ofFig. 4. Figs. 6 to it inclusive represent the various positions whichthe parts occupy during the running ant. reversing of the motor. Figs.Hand 13 are views similar to Figs. 4 and showing a modified form. Figs.and

15 are diagrammatic views. ,Fig. 16 is a View similar to Fig. 13, butshowing another modification of the device, and Fig. -17 is a partsectional View of Fig. 16.

In Fig. 1 a is the vertical contact shaft for the ignition driven fromthe crank shaft by means of two bevel gears. and running in a sleevebearing 2. At the upper end of this shaft and rigidly connected theretois a flanged collar 7) (Figs 1, 3,4) on which the insulator (Z, 1. 3, l,5) is secured by means of the two screws c (Figs. 3, 5). The insulator dis provided in known manner with a recess for receiving the confreely ina corresponding recess in the insulator (Z. Besides the recessmentioned, the part 03 has a further recess of oblong shape in a radialdirection. which serves to receive the ball The lug h (Figs. 1, 4)projects into this recess and causes the ball 9, when.

the engine is stopped or only running slowly, to roll toward the axis ofrotation of the insulator' as shown in Figs. 4 and Under the weight ofthe ball 9 the spring f will bend down'until its platina contact touchesthe platina'stud i fitted in the flanged sleeve 6 whereby a conductiveconnection is efiected between the flanged sleeve 2) and the contactor6. When the speed of the contact shaft a rises to or above a certainvalue, the ball 9 will, owing to centrifugal force, roll up on lug h(Fig. 1)thereby releasing spring which will now return into its originalposition andinterrupt the contact 'at stud i. The ball 9 will remain inthe position shown in Fig. 1 as long as the speed suffices to maintainthe centrifugal force necessary therefor. The lug h is of such a shapethat the ball will roll off only at a very low speed, shortly before themachine stops altogether.

On the insulator d is secured a cover disk (Figs. 1, 2) by means ofthree screws (Z, Z, Z) of which the one Z is fitted in the contactor eand thus produces a metallic contact between the latter and the coverdisk 76. In the center of the latter is the shouldered stud-m, thelowermost cylindrical portion of which serves as a center for the disk nwhich loosely engages the same. This dish is provided with an armprojecting to the left (Figs. 1, 2). By means of a spiral. spring(Fig. 1) the disk p is forced against the disk n, the disk 79 having asquare hole in its center, which engages a square section of the stud m.

When the shaft a revolves the disk 11. will owing to the frictionagainst /a and p be in clined to follow such rotation, but this movementis prevented by the fork g, which is provided on a suitable part of theengine (Fig. 2), and the two ends of whichembrace the projecting arm ofthe disk a. As the fork (7 and the arm n serve to conduct a current fromthe mass of the motor to the contactor e which is in metallic contactwith the d sk n, the parts where the fork q and the disk a meetincontact are provided with non-oxidizable contact buttons. As the arm nwill abut-against one of the branches of the fork g as long as theengine is running a permanent good metallic connection be tween the massand the contactor e is maintained. From the latter the current isconducted in known manner by means of a sliding contact r, such as shownin Figs. 1 and .2, to the ignition device. This sliding contact is, asusual, insulated from the housing a, which is cup shaped and inclosesthe whole attachment, to which it is secured. The

housing can be rotated by means of a lever t a container for lubricantand provides all frictional parts with the same by means of a wick. Inorder'to prevent the small particles which wear off from the slidingcontact from getting into the lubricant, an annular groove is providedaround the said container, in the bottom of which the small particleswill fall and pass therefrom through a number of holes provided therein.

The above described arrangement permits an immediate reversing of themotor without taking into consideration whether it is running slowly orat a high speed, and without having to observe any precautions, merelyby turning the housing 8 into one of its extreme positions. The twoextreme positions are determined by the abutting of lever t or byabuttingof the lug u (Figs. 2, 6-11) against fork g and.can therefore beeasily adjusted. v

In Fig. (i the principal positions of the housing 8 are indicated byRoman charactors I, II, III, TV. For adjusting the ignition for theforward revolution of the motor the stroke of the lever between thelimits I and III is employed, the position I corresponding to anignition exactly at the dead point, whereby the shaft a is supposed torevolve in the direction of the clock. Consequently when the lever 25 isturned in the direction of the arrow marked Forward the ignition willhave a lead and the speed of the engine will accordingly be increased.Position III corresponds to the maximumlead of the ignition. From Figs.'6 and 7 it is evident, that'the width of the slots in the housing 8 hassuch a size, that its edges marked as and 3 will admit of the lever tbeing adjusted within the-positions I and III, without the arm a comingin contact with either of the said edgeszr or y. If however the lever 15is moved beyond theposition III. into the position IV shown in Fig. 8,the edge a: will push the armit forward and thereby interrupt thecontact with the fork q. As thereupon the ignition will cease in thecylinder owing to lack of current, the speed of the motor will quicklydrop and the latter would come entirely to a standstill if the ball 9,which was held by centrifugal force until now in the position shown inFig. 1, did not roll down from lug. 4 and reach the position shown inFig. 4. The current which is now "nonsensinterrupted betwecn the arm nand the tori; g has by means of the contact pin a and the spring fanother conducting passage to the ontacto-r c. he first of the renewed.ignitions will owing to the increased lead of the ignition inconsequence of the lever 5' being in position IV, of the inward strokeof the piston, so that the latter must reverse its direction of travelbefore it has reached the dead point. Togcther with the crank shaft alsothe igni tion contact shaft a. will be reversed. The arm a willconsequently leave the stop at m and l ollow the rotation of shaft auntil it strikes against the end of the torlr g. lit now as the speedincreases theball g is again moved to break the contact at the stud i,the current is conducted to the con tactor c in the sainenianner duringthe forward rotation, over the fork q and arm a; with the onlydillerence that during the reversed rotation the other end of the fork,in the drawing the lower one, will conduct the current (Fig 9). Theposition of the lever t, being the same in Fig. 9 as in Fig. 8corresponds for the reversed rotation with an ignition spark at theupperdead point. The moment of the ignition is adjusted for the reversedrotation between the ultimate positions IV and 11 (Fig. 6) an advance ofthe lever t in the direction of the arrow marked Backward increasing thelead of the ignition. Atpoint H the maximum lead reached, the stop 1 ofthe slot in the housing being close to the arm a without coming incontact with the same (Fig. 101). When the lever t is turned beyondpoint ll, into position T Fig. 11) the amp. n is moved by the stop gand-the contact between the arm n and the fork q is interrupted. Thereversing ot' the direction of rotation of the machine is now eiiectedin exactly the same manner as hereinbetore described for the forwardrotation.

Instead. of the ball '9 of course any other suitable neansmay beemployed, which will under action of the centrifugal force interrupt anexisting circuit. Also the autoinatic reclosing ot the circuit,interrupted during the reversing may be obtained after the direction ofrotation of the engine has been reversed by other means than thosespecifiedin the description.

In the design hereinbetore described the rolling down of the ball merelydepends on a certain speed of rotation and not on the relative angularposition of the fiber part cl to the sliding contact r. In the formerinstance the ball produces a contact only at the stud 2'. whereas thecircuit is closed only when the sliding contact 7* is reached by thecontactor e, at a predetermined relative angular position of the crankshaft running synclironously with the fiber part d. if the ball rollsdown however only after the parts occur during the first half e and 7have met in contact the circuit is closed at any moment during thecontact period between the parts 6 and r. Hereby however the closing ofthe circuit may be retarded in such a manner that the ignition occurs ata position of the piston unsuitable for the reversing of the engine. Forif the contactor e meets the slip contact '1 when the crank is under anangle of to the dead point, the contact will cease only at the deadpoint, as the period of contact must for practical reasons extend. overa travel of the crank around an angle of 60".. If the ball rolls down ata position of the crank of 20 before the dead point the ignition, whichfor reliable effect should occur at about 60 to 35 before the deadpoint, will be too late and the machine will probably stand still. Thisprobability amounts however only to 1:12, so that the reliability of theeffect remains considerable and is suihcient. in most instances.

For obtaining an absolute security for many other purposes the followingdevice has been designed: As may be from Figs. 12 and 13 the contactor eis titted'in a til-shaped metallic part 0 from which it is insulated.The elements 6 and v are secured by means of two screws to the fiberpart (Z. The metallic part c has two projections lying on opposite sidesof the party 6 and these projections extend flush with the cylindricaleirci'nnference of the libel" part (Z, whereby the part v forms byitself a contactor. To this contact piece is attached the spring f,which, as the part c is insulated. from the part 6, will contrary to thehereinbefore described design, have no metallic connection with thelatter. The cont actor e is as previously, conductively connected bymeans of a screw Z (Fig. 1) with the cap is, the latter not coming incontact with the contact piece '21, as Will be evident from Fig. 12. Thecurrent can thus be conducted from the mass of the engine to thecontactor e merely through the cap 7.: over the'parts n and 9 (Fig. 1)while the current can flow to the contact piece 2) only through thespring over the contact stud 5. During the ordinary runot" the enginethe contact piece 1; will be without current, as the ignition current isconducted over the contactor 6. Only when for the purpose of reversingthe engine, theignition circuit is interrupted between the parts 9 and'n, the part v will receive a current after the ball 9 has rolled downin consequence of the speed having dropped sufficiently.

In Figs. 14; and 15 the flow of the current in the twojust describedinstances is illustrated, the live parts, through which the currentflows being marked with thick lines,

y the mass, A a switch between the mass and the source of current. Z isthe ignition plug inserted in the secondary circuit. The other letterscorrespond with the same letters in the,other figures.

Fig. lat illustrates the connections during 'the ordinary run of theengine. From the v peculiar feature that it will prevent the ignitionoccurring at an unsuitable position of the crank, by preventing thecircuit from being closed by the ball rolling down as long as the partse and r are in contact.

As may be seen from Figs. 13 and 15 two current impulses will reach thecontact piece oduring each revolution. In the reversing positions of thehousing 8, as shown in Figs. 8 and 11, the one impulse will occur at anangle of the crank to the dead point of 60, while the other impulse willmeet exactly with the dead point. If the'ball rolls down while the part0' is gliding on the fiberthe front leg of r (with relation to the senseof rotation) will first close the circuit with the slip contact r. Inconsequence thereof the ignition will take place at 60 ahead of the deadpoint and the machine will be reversed. If however the ball rolls downwhile the parts 1* and e are in contact, the rear leg of the part 1:will first close the circuit. Even if the ignition now occurringsomewhat. behind the dead point, gives the fly wheel a fresh impulse inthe same directions of rotation, as'it had until then, the accelerationowing to the considerably belated ignition is so small, that thefollowing ignition, which occurs at 60 ahead of the dead pointwill-certainly reverse the engine. Even such ignition in the dead pointposition may be avoided by simple means. If, as shown in Fig. 16, thecontact piece 12 is divided into two parts 0 and o, which are not inmetallic contact with each other, and each of these parts is providedwith a contact spring, of the kind as described above, it only need bearranged that the ball on reversing will conduct current to one of thesehalves only, and always to the forward one, with relation to thedirection of rotation. .This is very easily obtained by widening therecess proi ided in the fiber part at for the ball (cfr. Figs. 16 and17). As during the running of the engine the ball will always be lyingagainst the rear wall of the recess, with relation. to the direction ofrotation (see arrow) it will rise on the contact spring f ofthe rearcontact .piece with relation to the direction of rotation (Figs. 16 and17); when the direction of rotation is reversed, the ball 9 must rollagainst the 0pposite wall of the recess, thus resting on the spring f.

Having thus described myinvention, what I claim and desire to secure byLetters Patent of the United States is:

1. In a combustion engine, in combination, a timer shaft adapted to bedriven by the engine, a circuit-controlling contact carried thereby, acircuit-controlling spring electrically connected to saidcircuit-controlling contact, said spring normally occupying its opencircuit position, a movable member normally out of engagement with saidspring and adapted when the speed of the engine passes below apredetermined value to move into engagement with said spring to causethelatter to occupy its circuit closing position, a rotatablecircuit-controlling member electrically connected to saidcircuit-controlling contact, manually operated means to move saidcircuit-controlling member to cause it to break its circuit I andautomatically operated meansfor causing said member to close its circuitwhen the direction of rotation of said timer shaft is reversed.

2. In acombustion engine, in combination, a timer shaft adapted to bedriven by the engine, a circuit-controlling contact carried thereby, acircuit-controlling spring electrically connected to saidcircuit-controlling contact,said spring normally occupy ing its opencircuit position, a movable mem- ,ber norm-ally out of engagement withsaid spring and adapted when the speed of the engine passes below apredetermined value -to move into engagement with said spring to causethe latter to occupy its circuit closing position, a rotatablecircuit-controlling member electrically connected to saidcircuit-controlling contact, a fork-shaped contact piece provided withtwo stopsadapted to be electrically engaged by said member dependingupon the direction of rotation of said timer shaft, manually operatedmeans to move said circuit-controlling member to cause it to break itscircuit and automati-,'

cally operated means for causing said memher to close its circuit whenthe direction of rotation of said timer shaft is reversed.

3. In a combustion engine, in combination, a timer shaft adapted to bedriven'by the engine, a circuit-controlling contact carried thereby, acircuit-controlling spring electrically connected to saidcircuitcontrolling contact, said spring normally occupying its opencircuit position, a movable member normally out of engagement with saidspring and adapted when the speed of the engine passes below apredetermined value to move into engagement with said spring to causethe latter to occupy its circuit closing.

position, a contact lever rotatably secured to thetimer shaft, meanstending to rotate said lever with said shaft, a fork-shaped contactpiece provided in the ignition system and provided with two stops forengaging the contact lever and preventing rotajtion thereof and manuallyoperated means shaft, means tending to rotate said lever with said saidshaft, and a fork-shaped contact piece'provided in the ignition systemand. provided with two stops for engaging the contact lever andpreventing rotation.

thereof, said-device having a rotatively adjustable case for removingthe contact lever from the stop when the case is adjusted into thereversing position.

5. In a combustion engine, in combina- V tion, a timer shaft adapted tobe driven by the engine, an electrical contact carried thereby, a pairof electrical contacts carried by said shaft, said pair being insulatedfrom said first mentioned contact and from each other, spring contactsconnected to said pair of contacts, contact points adapted to be engagedby said spring contacts, and a ball adapted to engage one or the otherof said springs according to the direction of rotation of said shaft tocause the engaged spring to move into contactwith its associated contactpoint.

In witness whereof I have hereunto set my hand this twenty-first day ofSeptember nesses.

. WILLY SECK.

Witnesses: v

HENRY HASPER, WOLDEMAR HAUPT.

Copies of this patent may be obtained for five centi each, by addressingthe Commissioner of Patents,

Washington, 10.1).

v1909 in the presence of two subscribing wit-

